Aiohttp Framework Vulnerability in Asynchronous HTTP Client/Server
CVE-2026-34514

2.7LOW

Key Information:

Vendor

Aio-libs

Status
Aiohttp
Vendor
CVE Published:
1 April 2026

What is CVE-2026-34514?

The Aiohttp framework, an asynchronous HTTP client and server for Python's asyncio, has a vulnerability related to the 'content_type' parameter. This flaw could allow an attacker to inject additional headers into responses by manipulating the parameter. This issue has been resolved in version 3.13.4, urging users to update their installations to ensure protection against such exploits.

Affected Version(s)

aiohttp < 3.13.4

References

https://github.com/aio-libs/aiohttp/security/advisories/G...
x_refsource_CONFIRM
https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf...
x_refsource_MISC
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4
x_refsource_MISC

CVSS V4

Score:
2.7
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.